Document feeder and control system



1965 R. L. SWARTZ ETAL 3,201,114

DOCUMENT FEEDER AND CONTROL SYSTEM Filed May 11, 1961 2 Sheets-Sheet 1INVENTORS RICHARD L. SWARTZ BY WILLI D.HIGHSI1A ITH nan? /{w-. ATTORNEYSAug. 17, 1965 R. L. SWARTZ ETAL 3,201,114

DOCUMENT FEEDER AND CONTROL SYSTEM Filed May 11, 1961 2 Sheets-Sheet 2INVENTORS RICHARD L. SWA .52 5: WILLIAM umews H p F" BY 22m, iml w WMATTORNEYS United States Patent 3,201,114 DUCUMENT FEEDER AND (ZUNTROLSYSTEM Richard L. wartz and William ll). Highsmith, Columbia, SAIL,assignors to Universal Business Machines, line, Columbia, 8.0, acorporation of South Carolina Filed May 11, 1961, Scr. No. 99,459 6Claims. {CL 271-111) This invention relates to a device or machine forfeeding documents, one at a time, from a stack of documents to alocation adjacent the stack where they are delivered for further use.

The term documents as used herein refers to sheetlike articlesgenerally, such as checks, vouchers, receipts, paper money, and thelike, including envelopes which may contain sheet material. Ourinvention is especailly useful for sorting mail.

While not limited to such use, this invention is especially useful indocument sorting machines of the type disclosed in US. Letters Patent2,707,569 issued to LeRoy J. Benson, and in our copending applicationSerial No. 686,745, filed September 27, 1957, now Patent No. 2,984,481.Machines of this type include a bin for receiving a stack of documentsto be sorted, the stack being supported upon a vertically movable bottomor platform in the bin, a feeding device for removing the top documentfrom the stack and feeding the document to a conveying guideway adjacentthe stack, a keyboard arranged adjacent the stack and having a number ofkey-controlled devices for selecting and operating any one of a numberof tiltable gates arranged at spaced stations along the length of theguideway and for simultaneously operating the feed device to move theuppermost document into the conveying guideway. As the document isconveyed along the guideway and reaches the selected station, the tiltedgate at the selected station will deflect the document downward into asuitable storage bin.

Our present invention is also useful in sorting machines where thedocuments or sheet-like articles are supported on one edge in ahorizontal stack within a supply receptacle which is provided in thebottom wall thereof with conveyor belts or chains. Examples of suchhorizontal stack arrangements provided with endless conveyor belts orchains in the bottom wall thereof are shown in US. Patents to Cadden1,442,126 and Davidson 2,089,946. The present invention embodiesimprovements over these prior arrangements.

The present invention is concerned with the arrangement for feeding thedocuments from the top of the stack or the face of the stack, into thedelivery guideway and involves improvements over the arrangementdisclosed in our copending application Serial No. 686,745, filedSeptember 27, 1957, now Patent No. 2,984,481.

The feeding arrangement of this invention involves the use of a suctioncup or nozzle for picking up the face document (the document at the topof the stack) and transferring it to a delivery station adjacent thestack.

An object of the invention is to improve the arrangement for mountingand operating the suction cup.

Another object is to provide simple and effective means for preventingtwo or more documents from being fed or removed from the top of thestack during any one operating cycle.

Another object is to devise an improved stack conveyor arrangement forfeeding a horizontal stack of documents to the pick-up position of thesuction cup and to insure proper alignment of the leading edges of thedocuments at the pick-up station.

Still another object is to devise a novel control system for effectingoperation of the different elements of the feeder in proper sequence ineach operating cycle.

A preferred embodiment of the document feeder and its ifidhll l controlsystem is described herein in connection with the accompanying drawingsin which:

FIGURE 1 is a side elevational view of the feeder in diagrammaticrepresentation, as applied to the feeding of documents from a verticalstack, together with a diagrammatic showing of the control system;

FIGURE 2 is a fragmentary view of part of FIGURE 1 showing the suctioncup mounting depressed into the pick-up position;

FIGURE 3 is an end view of some of the elements shown in FIGURE 1 asseen from the left side of FIG- URE 1;

FIGURE 4 is a view similar to FIGURE 3 but showing the feeder adapted tofeed documents from a horizontal stack of documents; and,

FIGURE 5 is a plan view of the supply receptacle and conveyor for thearrangement shown in FIGURE 4.

In the embodiment illustrated in the drawing, a suction cup 1 issupported at the end of a supporting stem in the form of a suction tube2 which is arranged to slide lengthwise in a bore formed in a bearingblock. 3, the cup 1 being supported on the lower end of tube section 2aarranged at right angles to the main section 2 as shown in the drawing.The cup supporting stem, tube 2, is normally held in a horizontalposition with its axis parallel to the direction in which documents areto be removed from the stack DS. As shown, the cup I normally is held inan elevated position above the top of the stack and with the plane ofits mouth at the proper elevation to pass between two feed rollers R1and R2 at the entrance to a delivery trackway located at the right sideof the stack.

The bearing block 3 is mounted on a fixed support to be tilted about atransverse axis 4- to shift the suction cup 1 from its normal positionshown in solid lines, to the pick-up position 1 shown in dotted lines,where it engages the top of the stack DS. Pick-up cup 1 is made offlexible material, such as rubber, or plastic material, and it may besurrounded by a protective casing in the form of a rigid shell 2bsupported from tube section 2a, the mouth of the cup extending below theshell as shown at 10.

A rigid bar 5 is attached to the bearing block 3 and extends forwardparallel to the suction tube 2 and at one side thereof. Bar 5 is slottedat St: near the outer end thereof, and a stop element 6 is adjustablyclamped to the bar 5 between the tube 2 and the bar by means of clampingscrews 6a passing through the slot 5a. A stop member 7 is secured to thesuction tube 2 .and limits the lengthwise movement of tube 2 byengagement with the adjustable stop 6 in one direction and with the endof block 3 in the other direction. The suction cup 1 is maintained inits extended position shown in FIGURE 1 by a tension spring 8 attachedat one end to a pin 5b carried by the bar 5 at its outer end, the otherend of spring 8 being attached to a pin 8a carried by a rigid bar 7amounted on stop 7 and extending parallel with the bar 5, the pin 8aextending laterally from bar 7a to a point below bar 5. The bar 70 has asliding fit in a slot formed in lug 3a extending down from block 3. Thisprevents tube 2 from rotating about its axis and thereby holds cup 1against such rotation.

The suction tube 2 and its mounting is rotated about the axis 4 from thehorizontal position shown in FIGURE 1 to the lower position of the cup 1by means; of a solenoid 9 mounted on a fixed part of the machine frameand having a plunger 9a connected through a link 1!) to one arm 11 of abell-crank lever having another arm. 12, the lever 11-12 being pivotedon a horizontal pin 13 supported by the fixed frame. When the solenoid 9is energized the plunger 9a moves inwardly and rotates the lever 11-12clockwise to depress the left end of the bearing block 3 in the mannershown in FiGURE 2. The right end of arm 12 is provided with a shoe 12awhich has sliding engagement with a wear plate 3b mounted on the block3. A tension spring 14 is connected to the bar 5 at the point 5c and isconnected to a fixed part of the frame above the point 5a such as thepin 13. Spring 14 normally holds the suction tube 2 and its support inthe position shown in FIGURE 1. Upward movement of the support isarrested by engagement of the arm extension 12b with a lug 15 extendingunderneath the portion 12b from a fixed part of the frame. As shown inFIG. '2, the lever 12 is not secured to the block 3, but has onlysliding contact therewith, so that contact between these two parts willbe interrupted if the inertia of hte moving parts (tube 2 and itsmounting) is sufiicient to overcome the pull of spring 14.

A cylinder 16 is mounted in axial alignment with the bore in the block 3by means of a bar connection 17 secured to the rear end of block 3 andholding the cylinder 16 in spaced relation with the rear end of theblock 3. The left end of cylinder 16 is open and the right end closed.The suction tube 2 extends out of the rear end of block 3, into the openend of cylinder 16 and is attached to a piston 18 operating within thecylinder 16, so that when a vacuum is established in the right end ofcylinder 16 the tube 2 and the suction cup 1 is moved to the right. Theright end of cylinder 16 is connected to a suitable vacuum pump by wayof flexible tube or conduit 19, cut off valve being interposed in theconnection to control the times at which a vacuum is applied andremoved. The valve is shown diagrammatically and comprises a fixed block24) having an aperture forming a portion of the conduit 19 and a movableblock 21 having face-to-face sliding contact with block 20 and having anaperture forming part of the conduit 19. The aperture in block 21normally is spring biased out of registry with the aperture in block2t), so that the vacuum connection is interrupted. A solenoid 22 isconnected to shift block 21 so that its aperture is in registry withthat in block 2% to establish the connection from the vacuum pump to thecylinder 16.

The bore within block 3 is larger than the outside diameter of suctiontube 2 and the tube is supported at the center of the bore by an annularbearing piece at each end of the bore, thus providing an annular chambersurrounding the tube 2 within block 3. A vacuum connection from a vacuumpump is established to this annular chamber by a second flexible conduit23 connected to an opening in the block 3 communicating with the annularchamber surrounding the tube 2. Conduit 23 is provided with a controlvalve like that in conduit 19 and formed of a fixed block 24 and amovable block 25 controlled by a solenoid 26. The valve 24-25 normallyestablishes a connection between the pump and the annular chamber whenthe solenoid is deenergized, and this connection is interrupted when thesolenoid is energized. Suction is applied to cup 1 through tube 2 bymeans of one or more holes 2c formed in the wall of tube 2 at a locationwithin the annular chamber of block 3 when the tube 2 is in its extendedposition. These suction holes are located so that they move out of block3 into the space between block 3 and cylinder 16 when the tube 2 is ator near the end of its feeding stroke. This admits ambient air to tube'2, thereby removing the suction on cup 1 and releasing the documentfrom the cup.

A vacuum responsive switch VS is connected in conduit 23 and is providedwith an armature (a) which normally engages contact (b) to energize acircuit to solenoid 9 and which responds to a certain magnitude ofvacuum in the conduit 23 to deenergize solenoid 9 and energize solenoid22 through a circuit to be described below.

The solenoid 9 is controlled by a pickup relay PR which in turn iscontrolled by two feed control relays FC1 and F02. Solenoid 9 isenergized from supply conductor 27 leading to armature (a) of a vacuumswitch VS, through the normally closed contact (b) of this switch,through the coil of solenoid 9 and through normally open contact 4i PR-aof pickup relay PR and back to supply conductor 23 leading to the otherside of the supply source. Energization of pickup relay PR closes itscontact PR-a and energizes solenoid 9 to move the cup 1 downwardly intopickup position.

The energizing circuit for feed solenoid 22 is completed from supplyconductor 23 through the normally closed limit switch 29 having anoperating arm extending into the path of a part of the suction cupsupport, in this case the cylinder 16, to be opened when the suction cupis moved downwardly into pickup position. The circuit continues fromswitch 29 through the winding of solenoid 22, through contact PC2-a ofrelay FC2, through contact VSc of vacuum switch VS when closed, and fromthe tongue (a) of switch VS back to the supply conductor 27. Thussolenoid 22 cannot be operated except when a vacuum is efiective in theconduit 23 and therefore in the suction cup 1.

The circuit for energizing soleniod 26 extends from supply conductor 27through the winding of the solenoid, through contact PC2-c of relay FCZ,and through the normally closed contact PR4) of pickup relay PR and backto supply conductor 28. It may be noted that solenoid 26 normally isenergized to cut off the vacuum connection to pickup cup 1.

The energizing circuit of pickup relay PR extends from supply conductor23 through the relay winding, through the normally open contact FC2-IJof relay FCZ, and through the normally open contact of limit switch '50,through the normally closed contact of a key switch 32 mounted in thekeyboard 33, and back to supply line 27. The normally open limit switch36 is held in closed position by a finger 7b carried by the stop 7mounted on the tube 2, when the tube is in its extended position asshown in FEGURE 1. Switch 36 is opened when the tube 2 moves in thefeeding direction, and at the end of its feeding movement the finger 7bopens the normally closed limit switch 31.

The energizing circuit for relay FC1 extends from supply conductor 27through a normally-open key contact 34 mounted within the keyboard andbeing operated by any key which effects final selection. This universalaction of contact 34 is represented by the operating bar 35 extendingentirely across the keyboard. From contact 3 the circuit of relay FC1continues through the winding of the relay to support conductor 28.

The initial energizing circuit for relay FC2 is completed from supplyconductor 27 through key contact 34, through the normally closed contactof relay FC1 through the normally closed contact FCZe of relay FC2, andthrough the relay winding to supply conductor 28. Upon operation ofrelay F02, a holding circuit for the relay is completed from conductor28 through the relay winding, through contact FCZ-d of the relay,through the normally closed contact of limit switch 31, and throughrelease key contact 32 back to supply conductor 27. This holding circuitis completed at contact (at) of relay F02 before contact (e) is opened.Opening of the initial energizing circuit of relay FCZ by opening of thecontacts of relay FO-l prevents subsequent feeding operation beforeselection by the operator.

Operation of the feeder through a complete cycle will now be described,it being understood that-the feeder as shown in FIGURE 1 is in itsnormal state and ready to be driven through a cycle initiated by theclosing of key contact 34.

Closing of key contact 34 energizes relays FC1 and FCZ in parallel,opening all normally closed contacts of these relays and closing allnormally open contacts. Opening of contact FC2c on relay FCZ deenergizessolenoid 26 which allows return of valve part 25 to a position to applyvacuum to the suction cup. Relay FC2 will be held in operated positionby the closing of a holding circuit at contact PC2d and will hold thiscircuit closed through the normally closed contact of retract switch 31until the circuit is disturbed. Closing of contact (12) of relay FCZenergizes pickup relay PR through extend switch 3% which is wirednormally open, but is held closed by the finder 7b in the extendedposition of the suction cup 1 and tube 2. Operation of the pickup relayPR energizes the pickup solenoid 9 which causes the suction cup mountingto rotate about the axis 4 to lower the cup from its normal or retractedposition to its depressed or pickup position. The tilting of cylinder 16opens the normally closed feed safety switch 29 to break the circuit tofeed valve solenoid 22 while'feed stem or tube 2 is away from its normal(horizontal) position. When the pickup head is in this down position,the suction cup engages the top or face document of the stack. The softmaterial of the cup conforms partly to the surface of the document andsuction in the cup draws it up and seals the mouth of the cup. When thepressure in conduit 23 reaches approximately 6 vacuum, the vacuum switchVS is forced in by atmospheric pressure, changing the position of theswitch to open the power circuit to pickup solenoid 9 causing the pickuphead to return to its normal or horizontal position and lifting the topor face document from the stack. The changing of switch VS also closesthe power circuit to feed valve solenoid 22 which, on operation, opensthe valve 29-21 to create a vacuum in cylinder 16. The piston 18 isforced by atmospheric pressure to move to the right and carrying tube 2and cup 1 along with it. The leading edge of the document carried by thecup is directed between the two feed rolls R1 and R2, and, substantiallysimultaneously, the suction on cup 1 is relieved when holes 2c in tube 2move out of the rear end of block 3. Near the end of the feed stroke,switch operating lever 7b engages the arm of retract switch 3l, andopens thisnormally closed switch, breaking the circuit to feed controlrelay FCZ, which causes return of all controls to normal positions. Allcomponents are then ready for another cycle of operation which occursupon the closing of key contact 34.

The suction control valve 2445 is not essential where operating cyclesare repeated in rapid succession, but this valve is desirable for thepurpose of preventing serious loss in vacuum in the pumping systemduring the time when the pickup head is being returned to extendposition and during times when the machine is idling.

Another optional feature is the provision of a cycle selector switch 36connected to bypass the normally open contact FCZ-b in the energizingcircuit of the pickup relay PR. This switch determines the position ofthe feed head between selections. With switch 35 open, operation of key32 effects full cycle operation as described above where the pickup headmoves from its normal position, picks up a document, feeds it towardsthe feed rollers Rl-QZ, and returns to its normal position. By closingswitch 36 the automatic operation is varied so that upon the returnstroke of the pickup head, the head automatically picks up anotherdocument and then returns to its normal position and remains there untilthe next selection by the operator.

Full cycle operation should be used where the documents are thick andheavy enough to require excessive time for the supply conveyor toadvance the stack into proper position for a subsequent pickupoperation. Since full cycle operation is slower than the three-quartercycle operation, the three-quarter cycle operation is used wheneverpossible.

The vacuum release key switch 32 is provided on the keyboard foroptional isolation of the feed head from the vacuum system. Theenergizing circuits for the feed control relay PCS! and the pickup relayPR are completed through the normally closed contacts of the vacuumrelease key switch 32. Opening of these contacts will deenergize both ofthese relays and effect closing of contact PC2-c on relay FCZ and theclosing of contact b on pickup relay PR which will energize solenoid 26to shift the valve part 25 to the position cutting 011 the connectionfrom the vacuum pump to the suction tube 2.

The document introduced between feed rolls R1 and R2 is delivered bythese rolls for further handling by other apparatus, such as a guidewayprovided with gates spaced along the length thereof which control thedistribution of the documents to diiferent storage bins, one examplebeing shown in the Benson patent referred to above. Feed roll R1 isdriven continuously from a suitable source and roll R2 is an idlerpressure roller bearing against roll R1. For this purpose roll R2 may besupported at each end upon a pivoted arm 37 which is urged toward theroll R1 by biasing spring 38. This arrangement is effective in feedingdocuments of various thicknesses.

The feed roll Rl preferably is formed in three sections which are spacedapart axially, and a pair of fingers 339 formed of stiff wire aresupported at their rear ends by a transverse rod 39a fixed to themachine frame and extend forwardly through the gaps between the centersec tion of the roll and the two outer sections. The fingers 39 extendforward from the rod 39a above the level of the plane of contact betweenrolls R1 and R2 to a point in front of these rolls and then are inclineddownwardly beneath the cup 1 and then upwardly for a short distanceeyond the cup. 1

In moving from its normal position to pickup position, the cup 1 passesdownwardly between the fingers 39 to the pickup position, and when itreturns to the normal position shown in FIGURE 1, with the documentadhering to the cup, the fingers 39 effect transverse buckling of thedocument which is effective in dislodging another document which may beadhering to the lower face of the document carried by the cup. As thecup moves from its normal position in the feeding direction, thebuckling of the document becomes less and less due to the shape offingers 3%, so that the buckling does not interfere with the leadingedge of the document being introduced between rolls R1 and R2.

It will be understood that the vertical stack of documents shown inFIGURE 1 is supported in a suitable receptacle, and the top of the stackis maintained at a predetermined level below the fingers 3? by apparatuswell known in the art, see, for example, the Benson patent referred toabove.

FIGURE 4 is an end view of certain feeder parts, as in FIGURE 3, andshowing how the feeder is arranged to operate in connection with ahorizontal stack of documents. In this arrangement, the documents aresupported within a fiat tray 4% extending horizontally and at rightangles to the feeding axis of the feeder. Thus the feeding axis of thefeeder in FIGURE 4 is normal to the plane of the paper and thelongitudinal axis of the tray 4b is parallel with the plane of thepaper. As shown in FIG- URE 4 the documents D are supported on edge fromthe bottom of the tray 44 and they are inclined at an angle of about 45to the bottom of the tray, the rear or bottom end of the stack beingsupported by a follower element 41 having a forward face which isinclined about 45 to the horizontal. The horizontal stack of documentsis conveyed towards the feeder by means of a pair of endless conveyorelements 42 mounted in the bottom of the tray and serving to support thelower edges of the documents. These endless conveyors may take the formof endless belts as shown in the Davidson Patent 2,089,946 or as endlesschains as shown in the Cadden Patent 1,442,126. These two conveyors aredriven by a suitable motor 43 to convey the horizontal stack towards thefeeder. The follower 41 has frictional engagement with the conveyorelements and moves along with the stack. At the forward end of the traythe feeder is tilted at a 45 angle so that the pickup cup 1 faces thetop or face document at the front end or top of the stack. As explainedabove, a suitable sensing finger and control circuit may be provided tocontrol the operation of the conveyor motor to maintain the front end ofthe stack at the proper position for operation of the feeder.

For the purpose of maintaining the documents in the stack with theirleading edges aligned in the same plane, the endless conveyor elements42 are arranged inclined to the side walls of the tray 40. As shown inFIGURE 5, the conveyor elements 42 are arranged at an angle to the sidewalls such that the rear ends of the conveyor elements are at a greaterdistance from the side wall 40a than the forward ends of the conveyor.By this arrangement the documents are shifted laterally towards the sidewall 40a as the stack is moved forward.

We claim:

1. A device for transferring documents one at a time from the top of astack of documents to a discharge station adjacent said stackcomprising, a suction cup, an elongated stem carrying said cup at oneend thereof, mounting means supporting said stem for pivotal movementabout a transverse axis and for longitudinal sliding movement of thestern, resilient means acting on said stem for holding said cup in anormal position elevated above the top of said stack, resilient meansacting on said stem to hold said stem at one end of its longitudinalmovement with said cup positioned to pick up the face document of thestack, motive means connected to the other end of said stem foreffecting longitudinal movement of said stem in the desired direction oftransfer of documents from the stack, means for establishing a vacuumwithin said cup upon downward movement of said cup, and means forinterrupting the vacuum connection upon completion of the axial movementof said stem from the normal position of said cup to the dischargeposition.

2. A device according to claim 1 wherein said stern comprises a suctiontube connected to said cup, and said mounting means comprises a bearingblock having a bore receiving said tube and providing an annular spacesurrounding the tuhe within the block, a vacuum connectioncommunicatingwith said annular space, and at least one coupling hole inthe wall of said tube connecting the bore of the tube with said annularspace.

, 3. Adevice according to claim 2 wherein said coupling hole ispositioned to move out of said bearing block and be exposed to theatmosphere at the end of the feeding movement of said stem.

4. A device according to claim 1 wherein said motive 4 means comprises acylinder mounted in axial alignment with the rear end of said stem andhaving a piston connected with said stem, and a source of differentialpressure connected with said piston for eifecting transfer movement ofsaid stem.

5'. A device according to claim 1 and including a pair of cooperatingfeed rollers located at said discharge station and having contact witheach other substantially in the plane of the mouth of said cup, a pairof resilient fingers extending from said feed rolls on opposite sides ofsaid cup, said fingers being mounted to a fixed support adjacent saidfeed rolls and extending towards said cup for a distance at an elevationabove said plane, and then being inclined towards the face document, andhaving end portions inclined away from said document at a point betweenthe face document and the mouth of the cup, said cup, in moving topickup position, passing below said fingers to pick up the facedocument, and said fingers operating upon return of said cup to itsnormal position to cause transverse buckling of said document.

45. A device for transferring documents one at a time from a firststation to a discharge station comprising, a suction cup, means mountingsaid suction cup for movement from said first station to said dischargestation, a connection for applying vacuum pressure to said cup to hold adocument against the mouth of said cup, normally inactive transfer meansfor effecting movement of the cup from said first station to saiddischarge station, and means responsive to vacuum pressure applied tosaid cup and being operative when said pressure reaches a predeterminedvalue for energizing said transfer means, whereby said transfer means isoperated only when a document is carried by said cup and remainsinoperative when a document is not carried by said cup.

References Cited by the Examiner UNITED STATES PATENTS 1,548,000 7/25Finigan 271-18 2,138,306 11/28 Patrick. 2,161,124 6/39 Babicz. 2,222,45911/40 Backhouse 27126 2,236,363 3/41 Backhouse 27126 ROBERT B. REEVES,Acting Primary Examiner.

ROBERT A. LEIGHEY, ROBERT E. PULFREY,

RAPHAEL M. LUPO, Examiners.

1. A DEVICE FOR TRANSFERRING DOCUMENTS ONE AT A TIME FROM THE TOP OF ASTACK OF DOCUMENTS TO DISCHARGE STATION ADJACENT SAID STACK COMPRISING,A SUCTION CUP, AN ELONGATED STEM CARRYING SAID CUP AT ONE END THEREOF,MOUNTING MEANS SUPPORTING SAID STEM FOR PIVOTAL MOVEMENT ABOUT ATRANSVERSE AXIS AND FOR LONGITUDINAL SLIDING MOVEMENT OF THE STEM,RESILIENT MEANS ACTING ON SAID STEM FOR HOLDING SAID CUP IN A NORMALPOSITION ELEVATED ABOVE THE TOP OF SAID STACK, RESILIENT MEANS ACTING ONSAID STEM TO HOLD SAID STEM AT ONE END OF ITS LONGITUDINAL MOVEMENT WITHSAID CUP POSITIONED TO PICK UP THE FACE DOCUMENT OF THE STACK, MOTIVEMEANS CONNECTED TO THE OTHER END OF SAID STEM FOR EFFECTING LONGITUDINALMOVEMENT OF SAID STEM IN THE DESIRED DIRECTION OF TRANSFER OF DOCUMENTSFROM THE STACK, MEANS FOR ESTABLISHING A VACUUM WITHIN SAID CUP UPONDOWNWARD MOVEMENT OF SAID CUP, AND MEANS FOR INTERRUPTING THE VACUUMCONNECTION UPON COMPLETION OF THE AXIAL MOVEMENT OF SID STEM FROM THENORMAL POSITION OF SAID CUP TO THE DISCHARGE POSITION.